Foam producers use aromatic polyester polyols in the production of polyurethane and polyisocyanurate foams. Currently, foam producers use hydrochlorofluorocarbons as blowing agents to produce polyurethane and polyisocyanurate foams. However, the use of hydrochlorofluorocarbons as blowing agents presents ecological problems. Therefore, in the future, foam producers will phase out the use of hydrochlorofluorocarbons.
Researchers have tried to develop alternate blowing agents to replace hydrochlorofluorocarbons. As a result of this research, pentanes and hydrofluorocarbons have emerged as suitable replacements for hydrochlorofluorocarbons. However, these hydrocarbons and hydrofluorocarbons have poor solubility in currently available polyols.
Accordingly, what is needed are aromatic polyester polyols that are suitable for use with hydrocarbon and hydrofluorocarbon blowing agents.